Generate URL slug

url_slug.rb

before_save :generate_title_slug

 protected

  def generate_title_slug
    title_slug = self.title.downcase.strip.truncate(50)

    #replace spaces with dashes
    title_slug.gsub! " ", "-"

    #blow away apostrophes
    title_slug.gsub! /['`]/,""

    # convert @ --> at, & --> and
    title_slug.gsub! /\s*@\s*/, "at"
    title_slug.gsub! /\s*&\s*/, "and"

    #replace all non alphanumeric, underscore or periods with dashes
     title_slug.gsub! /\s*[^A-Za-z0-9\.\-]\s*/, '-'  

     #convert double underscores, double dashes to single dash
     title_slug.gsub! /_+|-+/,"-"

     #strip off leading/trailing underscore
     title_slug.gsub! /\A[_\.]+|[_\.]+\z/,""

    self[:title_slug] = title_slug
  end